US2492183A - Acoustic device - Google Patents

Description

Dec. 27, 1949 M. c. ROSENBLATT zmmm ACOUSTIC DEVICE Filed-Jan. 25, 1946 IN V EN TOR.

. 97 Tommy Patented Dec. 27, 1949 UNITED STATES PATENT OFFICE 6 Claims.

(Granted under the act of March 3, 1883, as amended April 30, 1928; 370 0. G. 757) The invention described herein, if patented, may be manufactured and used by or for the Government for governmental purposes, without the payment to meof any royalty thereon.

The invention relates to a plug for the external orifice of the ear canal.

It is an object of the invention to provide a soft rubber plug which is adjustably self-supporting in the ear.

It is a further object of the invention to provide a novel adjusting means for adapting the device to different sized ears.

It is a further object of theinvention to provide a flexible ear plug having one end engaging the entrance to the ear canal and the other end engaging the ear crescent.

It is a further object of the invention to provide an adjustable support capable of general use, and able to resist a considerable amount of compressive force.

Whilethe ear canal is more or less opposite the ear crescentin the human ear, it enters the head at an angle of 25 or more to a line between the entrance to the canal and the anti-helix or crescent of the external ear. The flexibility of the stem of the ear plug comprising my invention effects a tight sealing of the entrance by the tip of the plug and a firm engagement of the crescent by the anchor because the stem can be bowed outwardly in an arc of 50 or 60 degrees between the canal entrance and the crescent.

The flexibility of the stem also increases its frictional resistance to the sliding movement of the anchor when compressive forces are applied at opposite ends of the device because the stem expands under such pressure. This feature has utility in any field where a light adjustable support is needed.

Further objects of the invention will appear from a consideration of the following description taken in connection with the accompanying drawing, in which:

Figure 1 is a vertical sectional view of a human ear taken longitudinally of the ear canal showing the ear plug in place;

Figure 2 is a longitudinal sectional view of the ear plug showing the proper method of adjustment by a pulling action;

Figure 3 is a plan view of the plug showing its response to compressive force;

And Figure 4 is a plan view of the plug showing the surplus material of the stem being severed after a desired adjustment has been made; and

Figure 5 is a detailed sectional view of a modiflcation.

As shown in the drawing, the ear plug comprises a top or closure portion H] adapted to engage the entrance II to the ear canal, a cylindrical stem l2 of uniform diameter and a movable ear-engaging portion or anchor l3 slidably engaged on the stem. The central part I4 of the anchor has a round bore [5 which fits snugly on the stem l2 when it is in unstressed condition. Wings l6 extend oppositely from the central part [4 and constitute means to engage the crescent of the ear. Their relation to the central part I4 is such that when direct pressure is applied to the wings IS the bore l5 tends to close at the end nearer the tip, thus increasing the friction between the stem and the anchor.

The entire device is made of soft rubber, either natural or synthetic, which permits it to assume the arcuate shape shown at I1 in Figure 1. This provides a light and comfortable pressure exerted at the correct angle both at the entrance to the ear canal and at the crescent or anti-helix at the anchor end. It also accomplishes the automatic locking of the anchor l3 in the position required to fit the ear of the person using the device.

As shown in Figures 2 and 3, the anchor l3 fits the stem I2 slidably and can be moved along the stem easily in a direction away from the tip I!) if the tip is held in one hand and a pulling movement is applied to the anchor I3. However, if the tip I0 is held in one hand and the other hand pushes wings I6 of the anchor toward the tip, the bore of the anchor has a tendency to close at the end 3 and grip the stem l2, and the pressure against the tip ID, as transmitted through the stem, tends to expand the stem l2 as shown at H! in Figure 3, thereby increasing the resistance to the motion of the anchor l3, and preventing movement of the anchor on the stem. The resistance produced to compressive force is sufficient to cause a practically permanent adjustment of the anchor on the stem as far as compressive force is concerned and thus an automatic and convenient adjustment to a particular ear is provided. After the adjustment has once been made, any surplus portion of the stem l2 can be cut off as shown at 20 in Figure 4, thus providing a plug which can be carried by the individual and slipped into the ear at any desired time without inconvenience or further adjustment.

It should be noted that the tip l0 does not go into the ear canal, it merely closes it off at the entrance II. This seal is more effective than those obtained by devices which go into the ear canal itself. Such devices set up irritations and there is danger of infection and injury since the ear canal becomes very tender directly beyond the entrance.

The plug is useful both as protection against sound in the case of so1diers, workers in heavy industries, or light sleepers, or to prevent the entry of water into the ears. A lubricant, such as petroleum ,gieil'y, may be used on the tip :or head of my device, although this is of no great importance unless it is used as a swimmers plug.

The adjustment of the plug should be made a little longer than the distance between the entrance to the ear canal and the crescent to produce the outward bowing of the stem I 2 shown at I! and enable the tip to engage the entrance to the ear canal at an inward angle or in alignment with the entrance. The device will also engage the crescent more firmly in a slightly bowed condition, and therefore stay in the ear better.

It will be obvious that the 'sli'dable connection between the anchor and stem is adapted to use a variety of adjustable supports where a moderate resistance to compression is required, such as would be furnished by a rubber stem of sum-- e'i'ent softness and flexibility to respond to the compressive force by bulging, and hence Jprevent sliding motion of the anchor.

Dne example of such use would be as a support orfitting Iorh'ea'ring aids, small head phones, etc. A form of my invention especially adapted for such uses is shown in Figure 5. 'In this embodi ment I2 represents the stem, 6 the anchor, and 21 a passage extending through the tip and stem and o ening through the side of the stem at a point just ahead of the anchor when in its short est position. At this point a clip would hold such a thing as a head phone to the device, the device serving as an ear fitting.

The tip ll] of my device is somewhat larger than ear plugs as ordinarily found in the art. This over-size tip engages onl the entrance to the canal, forming an e'fiective seal because the flexible, outwardly-bowed stein hold's'it at the pro er angle. This avoids both the liklihood of irri= tating the canal and the necessity of making the device in a plurality of sizes, at least three sizes being necessary in the ordinary plug.

While the effectiveness of the grip of the anchor on the stem is increased by making both members of soft rubber, a satisfactory connection can be obtained with considerable variation in the degree of hardness of one of the elements. In the ear plug the use of soft rubber throughout contributes to the low cost and simplicity of the device, providing at the same time comfort at the points of engagement with the ear, bowing of the stem to give both resilient pressure and correct angles of engagement with the tra'gus and antihelix and sufficient deformation under pressure to lock the anchor on the stem. Though the cy-' lindrical stem is convenient and effective, the stem could be made in other configurations, as flat or square.

Having thus described my invention, what I claim is:

1. An ear-engaging device comprising a tip and a cylindrical stem of uniform diameter, an anchor having a bore of substantially the same diameter mounted on the stem, said stem being laterally bendable under pressure and said anchor resisting movement airing the stem when compressive force is applied to the anchor and one end of the stem, the distance between the tip and the anchor being slightly greater than the distance between the points to be engaged.

2. A sound-"transmitting device adapted to be worn in the ear and comprising a tip, a stem, and a 'sli'dable anchor mounted on said stem, said anchor and said stem formed of a compressible material whereby pressure on the anchor and on one end of the stem expands the stem and prevents sliding motion of the anchor toward that end, said tip and stem having a sound transmitting passage.

3. An ear engaging "device comprising an elongated memberof resilient and compressible mate'- rial, one end of said member adapted to engage the entrance to the ear canal and the other end to engage the crescent of the ear, said device being longer than the distance between the points to be engaged, whereby the elongated member assumes an outwardly-bowed position when in place, ieifec tivel sealing the entrance to the canal and locking the device in place. v

4. An ear plug comprising an integral tip and stem of resilient and compressible material, and an anchor member of similar material slidable longitudinally of the stem.

5. An ear plug comprising an integral tip and stem of resilient and compressible material, an anchor member of similar material slidable longitudi'nally of the stem, and wings 'on the anchor member shaped to fit the crescent of the ear.

6. An ear plug com-prising an integral tip and stem of resilient and compressible material, and an anchor member Of "similar material surround= ing said stern and islifla bly and s'n'u'gly engaging the same.

MAURIGE C-. REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 322,003 Plessner July 14, 1885 750,625 Elliott Jan. 26, 1904 1,355,276 Schultz Oct. 12, "1920 FOREIGN PATENTS Number Country Date 456,207 Germany Aug. 4, 1928

Images